What is the center of the circle that has a diameter whose endpoints are (4, 1) and (-6, 5)?

Factor 4x 2 + 12x + 5 . (2x + 5)(2x + 1)

swat32

$4x^2 + 12x + 5=4x^2+2x+10x+5 \\ \\ =2x(2x+1)+5(2x+1)=(2x+5)(2x+1) \\ \\ \therefore4x^2+12x+5=(2x+5)(2x+1)$

8 0

2 years ago

Rida and elisa are each paid by the hour. rida worked 5 1\2. hours and earned 77. elisa worked 3 3\4 HOURS AND EARNED 60. WHOSE

skad [1K]

Rida:
5 1/2 :77
5.5 : 77
Divide both sides by 5.5 to get $/hour:
1:14

Elisa:
3 3/4:60
3.75:60
Divide both sides by 3.75 to get $/hour:
1:16

16 is bigger than 14 so Elisa earns more.

Hope this helps :)

5 0

3 years ago

Ten students begin college at the same time. The probability of graduating in four years is 63%. Which expanded expression shows

Lynna [10]

Answer: the answer is a!

Step-by-step explanation:

5 0

3 years ago

Read 2 more answers

Find 6m if m = 5/13<br><br> Please help<br><br> Leave your answer in fraction form please

gladu [14]

Step-by-step explanation:

or, 6m=5/13

or, m=5/13 ×6m

m=30/13

3 0

3 years ago

A random sample of 20 students yielded a mean of ¯x = 72 and a variance of s2 = 16 for scores on a college placement test in mat

Helen [10]

Answer:

The 98% confidence interval for the variance in the pounds of impurities would be $8.400 \leq \sigma^2 \leq 39.827$ .

Step-by-step explanation:

1) Data given and notation

$s^2 =16$ represent the sample variance

s=4 represent the sample standard deviation

$\bar x$ represent the sample mean

n=20 the sample size

Confidence=98% or 0.98

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population mean or variance lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

The Chi square distribution is the distribution of the sum of squared standard normal deviates .

2) Calculating the confidence interval

The confidence interval for the population variance is given by the following formula:

$\frac{(n-1)s^2}{\chi^2_{\alpha/2}} \leq \sigma^2 \leq \frac{(n-1)s^2}{\chi^2_{1-\alpha/2}}$

On this case the sample variance is given and for the sample deviation is just the square root of the sample variance.

The next step would be calculate the critical values. First we need to calculate the degrees of freedom given by:

$df=n-1=20-1=19$

Since the Confidence is 0.98 or 98%, the value of $\alpha=0.02$ and $\alpha/2 =0.01$ , and we can use excel, a calculator or a table to find the critical values.